Chapter 4: Energy and basics of cellular respiration

 Producer vs Consumer:

  • Producer - Makes their own food
  • Consumer - Eat other organisms for energy
Cycling of Nutrients and flow of Energy:

  • Nutrients are cycled meaning that they go from producers to consumers and then back to producers when they die off. 

  • Unlike nutrients, energy is not cycled. It flows in one direction: from the sun to producers to consumers and then out of the ecosystem. 

Types of energies:
  1. Kinetic energy - Energy in motion (ex: Roller coaster moving down a track)
  2. Potential energy - Energy stored in an object due to its position (ex: Roller coaster on the top of a hill)
  3. Chemical energy - type of potential energy; Energy released during a chemical reaction (ex: lighting a match)
  4. Light energy - Energy that is taken from the sun 

Free energy: Energy available to do work 


Endergonic vs Exergonic reaction : 

Endergonic: Builds a polymer by storing energy --> reactants have lower free energy than products

Exergonic: Breaks a polymer by releasing energy --> reactants have higher free energy than products 

Redox Reactions: 
 
Reaction that involves a transfer on electrons:
  • Oxidized Redox Reaction: Molecule loses electrons
  • Reduced Redox Reaction: Molecule gains electrons 

Electron Transport Chain:

A series of protein groups that transfer electrons from one to another through the use of Redox Reactions. The ETC is an important part of cellular respiration and in the production of ATP (energy molecule).  

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